98 CYCLOSTREMA. 



C. PROXIMA, Tryon. PL 33, fig. 4. 



Xarrowjy umbilicated, faintly striate, with a few indistinct spiral 

 lines below the suture, and numerous well defined ones on the base, 

 around the umbilicus the inferior stride stronger, surface smooth, 

 greyish white, suture impressed, whorls very convex, rapidly in- 

 creasing; periphery round, thin, slightly in contact. 



Diam. 2'2 mill. Off New England Coast; 843 fins. 



Said to be closely allied to C. basistriata, Brugnone. Described 

 by Prof. Verrill as C. affinis, preoccupied by Jeffreys for the pre- 

 ceding species. 



C. TENERA, Jeffreys. PL 33, fig. 6. 



Xarrowly. umbilicated, thin, semitransparent, lustreless, with 

 nearly microscopic spiral striae, which are wanting on the base and 

 replaced by a rugose or fretted appearance, pale yellowish white, 

 with a faint greenish tinge, suture very deep; whorls 4, convex; 

 mouth circular, peristome thin, slightly expanded. Diam. 2'5 mill. 



European Atlantic (Porcupine Exped.) 



C. SIMILIS, Jeffreys. PL 33, fig. 7. 



Moderately umbilicated, depressed turbinate, rather thin, glossy, 

 opaque, without sculpture; whorls 4J, convex, rapidly increasing, 

 suture wide and deep; mouth nearly circular, slightly appressed, 

 peristome thin. Diam. 1'25 mill. 



European Atlantic (Porcupine Exped.) 



C. VALVATOIDES, Jeffreys. PL 33, fig. 8. 



Narrowly umbilicated, rather solid, opaque, glossy, with a few 

 irregular growth-lines, yellowish white, spire with rather flattened 

 apex, suture deep; whorls 4, well-rounded; perist9ine considerably 

 expanded. Diam. 3'12 mill. 



European Atlantic (Porcupine Exped.) 



C. spnyERoiDES, S. Wood. PL 32, fig. 69. 



Xarrowly umbilicated, white, spirally costate; whorls three, rapidly 

 increasing, suture deep. Diam. 1-25. mill. 



Bay of Biscay ; 



Described as a fossil of the Crag, Button, England, and said to 

 be nacreous in the original diagnosis. 



